Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2022
Authors
Arne SteffenremAbstract
No abstract has been registered
Authors
Kirsten Tørresen Jukka Salonen Lars Olav Brandsæter Björn Ringselle Marian M. Weigel Eliyeh Ganji Bärbel GerowittAbstract
Book of Abstracts p. 213: The perennial creeping weeds Cirsium arvense (L.) Scop., Sonchus arvensis L. and Elymus repens (L.) Gould cause large problems in agricultural production in northern Europe. The management of these species is difficult in organic farming, but easier in conventional farming using herbicides. We collected and analysed literature on the response of these weed species to management practices in order to find knowledge gaps. C. arvense and E. repens are more studied compared to S. arvensis. Both C. arvense and E. repens have recently been the subjects of extended reviews. Elymus repens, a rhizomatous grass, is vulnerable to disturbance and competition due to weak seasonal dormancy, shallow creeping rhizomes and short-lived and low-spreading seeds. Tillage and mowing can effectively control E. repens, but efficacy varies between clones, seasons and treatment frequencies. Combined effects of direct control and competition from main crop/subsidiary crop merit further research. Cirsium arvense and S. arvensis are dicot species with creeping roots, with C. arvense roots being situated deeper in the soil than S. arvensis and both having deeper roots than the rhizomes of E. repens. Cirsium arvense can sprout from the intact root system even below the plough layer. Spring tillage has been shown to control C. arvense better than autumn tillage, and horizontal root cutter (prototype) have promising results on this species. Sonchus arvensis sprouts mainly in spring and summer thus indicating seasonal dormancy. Therefore, spring tillage controls S. arvensis better than autumn tillage. The effect of competition from main crop and subsidiary crops needs further investigation. While E. repens and C. arvense can be significantly controlled by a simple mechanical control strategy alone (repeated tillage and deep root disturbance, respectively), S. arvensis must be managed by a combination of different non-chemical methods. Identified gaps focus on the deep root system and sexual reproduction (C. arvense), the link between disturbance, competition, withering and dormancy in roots (S. arvensis), and the long-term effect of different integrated weed management strategies on the population dynamics (E. repens). We conclude that more research on all three species is needed, especially on the less studied S. arvensis. Keywords: Couch grass, creeping thistle, perennial sow-thistle, mechanical control, crop competition, cover crop, subsidiary crop Acknowledgements: This research was part of the project “AC/DC-weeds- Applying and Combining Disturbance and Competition for an agro-ecological management of creeping perennial weeds” funded within the ERA-Net Cofund SusCrop/EU Horizon 2020, Grant no. 771134.
Authors
Frode VeggelandAbstract
No abstract has been registered
Authors
Pekka E. Kauppi Gustav Stål Lina Arnesson-Ceder Isabella Hallberg Sramek Hans Fredrik Hoen Arvid Svensson Iddo K. Wernick Peter Högberg Tomas Lundmark Annika NordinAbstract
Planting new forests has received scientific and political attention as a measure to mitigate climate change. Large, new forests have been planted in places like China and Ethiopia and, over time, a billion hectares could become available globally for planting new forests. Sustainable management of forests, which are available to wood production, has received less attention despite these forests covering at least two billion hectares globally. Better management of existing forests would improve forest growth and help mitigate climate change by increasing the forest carbon (C) stock, by storing C in forest products, and by generating wood-based materials substituting fossil C based materials or other CO2-emission-intensive materials. Some published research assumes a trade-off between the timber harvested from existing forests and the stock of C in those forest ecosystems, asserting that both cannot increase simultaneously. We tested this assumption using the uniquely detailed forest inventory data available from Finland, Norway and Sweden, hereafter denoted northern Europe. We focused on the period 1960 – 2017, that saw little change in the total area covered by forests in northern Europe. At the start of the period, rotational forestry practices began to diffuse, eventually replacing selective felling management systems as the most common management practice. Looking at data over the period we find that despite significant increases in timber and pulp wood harvests, the growth of the forest C stock accelerated. Over the study period, the C stock of the forest ecosystems in northern Europe increased by nearly 70%, while annual timber harvests increased at the about 40% over the same period. This increase in the forest C stock was close to on par with the CO2-emissions from the region (other greenhouse gases not included). Our results suggest that the important effects of management on forest growth allows the forest C stock and timber harvests to increase simultaneously. The development in northern Europe raises the question of how better forest management can improve forest growth elsewhere around the globe while at the same time protecting biodiversity and preserving landscapes.
Authors
Jian LiuAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Tina Heger Jonathan M. Jeschke Catherine Febria Johannes Kollmann Stephen Murphy Line Rochefort Nancy Shackelford Vicky M. Temperton Eric HiggsAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Laura D. Ngau Sim S. Fong Kho L. Khoon Elisa Rumpang Harri Vasander Jyrki Jauhiainen Kim Yrjälä Hanna Marika SilvennoinenAbstract
Water table conditions in drained peatlands affect peat decomposition, fluvial carbon and greenhouse gas emissions, and plant growth in oil palm plantations. This study illustrates the spatial heterogeneity of soil moisture profiles in cultivated tropical peat under oil palm plantation and uncultivated secondary forest, using maps. At a study plot under each land use the geographical coordinates of sampling points, tree locations and other features were recorded. Peat soil samples were taken at depths of 0–50 cm, 50–100 cm, 100–150 cm and 150–200 cm, and their moisture contents were determined. Overall, soil moisture content was higher in secondary forest than in oil palm plantation due to land management activities such as drainage and peat compaction in the latter. Significant differences were observed between the topsoil (0–50 cm) and deeper soil layers under both land uses. Soil moisture maps of the study plots interpolated using geographical information system (GIS) software were used to visualise the spatial distributions of moisture content in soil layers at different depths (0–50 cm, 50–100 cm, 100–150 cm, 150–200 cm). Moisture content in the 0–50 cm soil layer appeared to be inversely related to elevation, but the correlation was not statistically significant. On the other hand, there was a significant positive correlation between soil moisture content and the diameters of oil palm trunks. Palm trees with negative growth of trunk diameter were mostly located in subplots which were relatively dry and/or located near drains. The results of this study indicate that soil moisture mapping using GIS could be a useful tool in improving the management of peatland to promote oil palm growth.
Authors
Saheba Bhatnagar Stefano Puliti Bruce Talbot Joachim Bernd Heppelmann Johannes Breidenbach Rasmus AstrupAbstract
Wheel ruts, i.e. soil deformations caused by harvesting machines, are considered a negative environmental impact of forest operations and should be avoided or ameliorated. However, the mapping of wheel ruts that would be required to monitor harvesting operations and to plan amelioration measures is a tedious and time-consuming task. Here, we examined whether a combination of drone imagery and algorithms from the field of artificial intelligence can automate the mapping of wheel ruts. We used a deep-learning image-segmentation method (ResNet50 + UNet architecture) that was trained on drone imagery acquired shortly after harvests in Norway, where more than 160 km of wheel ruts were manually digitized. The cross-validation of the model based on 20 harvested sites resulted in F1 scores of 0.69–0.84 with an average of 0.77, and in total, 79 per cent of wheel ruts were correctly detected. The highest accuracy was obtained for severe wheel ruts (average user’s accuracy (UA) = 76 per cent), and the lowest accuracy was obtained for light wheel ruts (average UA = 67 per cent). Considering the nowadays ubiquitous availability of drones, the approach presented in our study has the potential to greatly increase the ability to effectively map and monitor the environmental impact of final felling operations with respect to wheel ruts. The automated mapping of wheel ruts may serve as an important input to soil impact analyses and thereby support measures to restore soil damages.